diff --git a/java/com/google/gerrit/index/SiteIndexer.java b/java/com/google/gerrit/index/SiteIndexer.java
index 24b7a69..9c56396 100644
--- a/java/com/google/gerrit/index/SiteIndexer.java
+++ b/java/com/google/gerrit/index/SiteIndexer.java
@@ -15,12 +15,14 @@
 package com.google.gerrit.index;
 
 import static com.google.common.base.Preconditions.checkNotNull;
+import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.base.Stopwatch;
 import com.google.common.flogger.FluentLogger;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.MoreExecutors;
 import java.io.OutputStream;
+import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.RejectedExecutionException;
@@ -64,7 +66,7 @@
 
   protected int totalWork = -1;
   protected OutputStream progressOut = NullOutputStream.INSTANCE;
-  protected PrintWriter verboseWriter = new PrintWriter(NullOutputStream.INSTANCE);
+  protected PrintWriter verboseWriter = newPrintWriter(NullOutputStream.INSTANCE);
 
   public void setTotalWork(int num) {
     totalWork = num;
@@ -75,7 +77,7 @@
   }
 
   public void setVerboseOut(OutputStream out) {
-    verboseWriter = new PrintWriter(checkNotNull(out));
+    verboseWriter = newPrintWriter(checkNotNull(out));
   }
 
   public abstract Result indexAll(I index);
@@ -86,6 +88,10 @@
         new ErrorListener(future, desc, progress, ok), MoreExecutors.directExecutor());
   }
 
+  protected PrintWriter newPrintWriter(OutputStream out) {
+    return new PrintWriter(new OutputStreamWriter(out, UTF_8));
+  }
+
   private static class ErrorListener implements Runnable {
     private final ListenableFuture<?> future;
     private final String desc;
diff --git a/java/com/google/gerrit/pgm/MigrateToNoteDb.java b/java/com/google/gerrit/pgm/MigrateToNoteDb.java
index 07da3f7..61d7ed9 100644
--- a/java/com/google/gerrit/pgm/MigrateToNoteDb.java
+++ b/java/com/google/gerrit/pgm/MigrateToNoteDb.java
@@ -16,6 +16,7 @@
 
 import static com.google.common.base.MoreObjects.firstNonNull;
 import static com.google.gerrit.server.schema.DataSourceProvider.Context.MULTI_USER;
+import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.stream.Collectors.joining;
 import static java.util.stream.Collectors.toList;
 
@@ -39,6 +40,7 @@
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import com.google.inject.Provider;
+import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
@@ -141,7 +143,7 @@
           migrator.migrate();
         }
       }
-      try (PrintWriter w = new PrintWriter(System.out, true)) {
+      try (PrintWriter w = new PrintWriter(new OutputStreamWriter(System.out, UTF_8), true)) {
         gcAllUsers.run(w);
       }
     } finally {
diff --git a/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java b/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
index 0015268..acb7236 100644
--- a/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
+++ b/java/com/google/gerrit/server/index/account/AllAccountsIndexer.java
@@ -30,7 +30,6 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
@@ -60,7 +59,7 @@
 
   @Override
   public SiteIndexer.Result indexAll(AccountIndex index) {
-    ProgressMonitor progress = new TextProgressMonitor(new PrintWriter(progressOut));
+    ProgressMonitor progress = new TextProgressMonitor(newPrintWriter(progressOut));
     progress.start(2);
     Stopwatch sw = Stopwatch.createStarted();
     List<Account.Id> ids;
diff --git a/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java b/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
index 2823c2e..3474934 100644
--- a/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
+++ b/java/com/google/gerrit/server/index/group/AllGroupsIndexer.java
@@ -33,7 +33,6 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
@@ -64,7 +63,7 @@
 
   @Override
   public SiteIndexer.Result indexAll(GroupIndex index) {
-    ProgressMonitor progress = new TextProgressMonitor(new PrintWriter(progressOut));
+    ProgressMonitor progress = new TextProgressMonitor(newPrintWriter(progressOut));
     progress.start(2);
     Stopwatch sw = Stopwatch.createStarted();
     List<AccountGroup.UUID> uuids;
diff --git a/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java b/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
index 07399c6..307a23e 100644
--- a/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
+++ b/javatests/com/google/gerrit/httpd/raw/IndexServletTest.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.httpd.raw;
 
 import static com.google.common.truth.Truth.assertThat;
+import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.template.soy.data.SoyMapData;
 import java.net.URISyntaxException;
@@ -30,7 +31,7 @@
     }
 
     String getIndexSource() {
-      return new String(indexSource);
+      return new String(indexSource, UTF_8);
     }
   }
 
diff --git a/javatests/com/google/gerrit/util/http/testutil/FakeHttpServletResponse.java b/javatests/com/google/gerrit/util/http/testutil/FakeHttpServletResponse.java
index 2b1a07e..f6b3e30 100644
--- a/javatests/com/google/gerrit/util/http/testutil/FakeHttpServletResponse.java
+++ b/javatests/com/google/gerrit/util/http/testutil/FakeHttpServletResponse.java
@@ -25,6 +25,7 @@
 import com.google.common.net.HttpHeaders;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.nio.charset.Charset;
 import java.util.Collection;
@@ -106,7 +107,7 @@
   public synchronized PrintWriter getWriter() {
     checkState(outputStream == null, "getOutputStream() already called");
     if (writer == null) {
-      writer = new PrintWriter(actualBody);
+      writer = new PrintWriter(new OutputStreamWriter(actualBody, UTF_8));
     }
     return writer;
   }
diff --git a/tools/BUILD b/tools/BUILD
index 53f441a..73ecfb9 100644
--- a/tools/BUILD
+++ b/tools/BUILD
@@ -68,7 +68,7 @@
         "-Xep:CannotMockFinalClass:WARN",
         "-Xep:ClassCanBeStatic:WARN",
         "-Xep:ClassNewInstance:WARN",
-        "-Xep:DefaultCharset:WARN",
+        "-Xep:DefaultCharset:ERROR",
         "-Xep:DoubleCheckedLocking:WARN",
         "-Xep:ElementsCountedInLoop:WARN",
         "-Xep:EqualsHashCode:WARN",
diff --git a/tools/bzl/gwt.bzl b/tools/bzl/gwt.bzl
index 2adb7dd..b185214 100644
--- a/tools/bzl/gwt.bzl
+++ b/tools/bzl/gwt.bzl
@@ -15,7 +15,7 @@
 load("//tools/bzl:genrule2.bzl", "genrule2")
 load("//tools/bzl:java.bzl", "java_library2")
 
-jar_filetype = FileType([".jar"])
+jar_filetype = [".jar"]
 
 BROWSERS = [
     "chrome",
@@ -225,7 +225,7 @@
             default = Label("@bazel_tools//tools/zip:zipper"),
             cfg = "host",
             executable = True,
-            single_file = True,
+            allow_single_file = True,
         ),
     },
     outputs = {
diff --git a/tools/bzl/js.bzl b/tools/bzl/js.bzl
index d6d0c95..0997bcb 100644
--- a/tools/bzl/js.bzl
+++ b/tools/bzl/js.bzl
@@ -426,7 +426,7 @@
 
 def bundle_assets(*args, **kwargs):
     """Combine html, js, css files and optionally split into js and html bundles."""
-    _bundle_rule(*args, pkg = PACKAGE_NAME, **kwargs)
+    _bundle_rule(*args, pkg = native.package_name(), **kwargs)
 
 def polygerrit_plugin(name, app, srcs = [], assets = None, **kwargs):
     """Bundles plugin dependencies for deployment.
@@ -447,7 +447,7 @@
         name = name + "_combined",
         app = app,
         srcs = srcs if app in srcs else srcs + [app],
-        pkg = PACKAGE_NAME,
+        pkg = native.package_name(),
         **kwargs
     )
 
diff --git a/tools/bzl/license-map.py b/tools/bzl/license-map.py
index 476ccb9..ebe57f2 100644
--- a/tools/bzl/license-map.py
+++ b/tools/bzl/license-map.py
@@ -35,7 +35,7 @@
             continue
 
         handled_rules.append(rule_name)
-        for c in child.getchildren():
+        for c in list(child):
             if c.tag != "rule-input":
                 continue
 
diff --git a/tools/bzl/license.bzl b/tools/bzl/license.bzl
index f011446..d059216 100644
--- a/tools/bzl/license.bzl
+++ b/tools/bzl/license.bzl
@@ -39,7 +39,7 @@
     if target[0] not in ":/":
         target = ":" + target
     if target[0] != "/":
-        target = "//" + PACKAGE_NAME + target
+        target = "//" + native.package_name() + target
 
     forbidden = "//lib:LICENSE-DO_NOT_DISTRIBUTE"
     native.genquery(
diff --git a/tools/bzl/pkg_war.bzl b/tools/bzl/pkg_war.bzl
index 1a376e9..40dd769 100644
--- a/tools/bzl/pkg_war.bzl
+++ b/tools/bzl/pkg_war.bzl
@@ -14,7 +14,7 @@
 
 # War packaging.
 
-jar_filetype = FileType([".jar"])
+jar_filetype = [".jar"]
 
 LIBS = [
     "//java/com/google/gerrit/common:version",